Thanks to Google for sponsoring a portion of this video. To learn more about Google’s sustainability efforts, click the link in the description.

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We’ve all spent nights tossing and turning, trying to get comfortable, not able to sleep because the room is just too dang hot. So you point every fan you have at the bed, you flip the pillow to the cool side, and you feel tired and grumpy the next day.

Well, according to research published this week in the journal One Earth, those nights are going to get a  lot more common – for everybody.

We know that the temperature of a room can influence sleep, but these researchers wanted to see if the outside temperature can have similar effects. The research team, based in Denmark and Germany, used sleep data from worn fitness trackers, and they looked at two years of sleep data from more than 47,000 adults in 68 countries. And they paired each night of sleep with weather information from where the person was sleeping. And they found that on hot nights, people fell asleep later, woke up earlier, and slept less during the night.

In fact, when it was more than  30 degrees Celsius outside, people slept an average of 14 minutes less than usual. And if it’s more than 25 degrees out, the chances of sleeping fewer than 7 hours increased by 3.5 percentage points. The effect was even greater in people over the age of 65, and somewhat elevated for women of all ages. And in lower-income countries, the relationship between temperature and sleep was around three times stronger than for people from high-income countries. Plus, people in places with warmer climates experienced more sleep loss per degree than people in cooler climates.

Ok, so that’s just thinking about different temperatures from night tonight. But the whole climate is warming right now. So what’s that going to do to our sleep? Well, the study team estimated that by 2010, we had already lost an average 44 hours of sleep and have 11 extra nights of short sleep per year, just due to warming temperatures. And, yeah, of course it’s only going to get worse.

Depending on how much greenhouse gases build up, by the year 2099 we may be losing 50 to  58 hours of sleep and having on average 13 to 15 nights of short sleep per year just thanks to temperature.

Short sleep is associated with worse immune system function, elevated risk of cardiovascular diseases, memory problems, and depression. So more nights of shortened sleep is a big public health problem.

Plus, all of those hours of sleep aren’t going to be evenly distributed. They’ll affect people who live in climates that are already hotter and people in poorer or low-resource countries more than those in wealthier, cooler countries. And because many low-income countries are in regions that already have higher temperatures, the Global South may be in for a double whammy. So sleep may be just one more way that the climate crisis ends up worsening inequality.

One way of mitigating the climate crisis is by planting more trees to capture carbon in the atmosphere. But a paper published this week in Nature suggests that the crisis might be fighting back. There’s evidence that the amount of carbon being stored by tropical forests has slowed down because more trees are dying, but we don’t know which trees, how many, or why. Like, these aren’t trees we’re cutting down. These are trees that are just… dying.

Scientists are pretty sure that it’s related to the climate crisis, but it’s hard to tease apart which weapon it’s using to commit-tree murder and how that weapon is being wielded.

So an international team of researchers decided to take a closer look at rainforests in North Queensland, Australia. It would not be a good experiment to plant a bunch of trees and let them grow up and eventually die,  so you could see how long they lived and how that changed over time because it would take forever.

Instead, these scientists looked at surveys of how many trees of each kind were recorded living in different areas, and calculated the probability that any given tree would die in any given year.

That number was called the mortality risk, and the researchers used it to work out whether trees are more likely to die now than they used to be. That translates into a shorter lifespan. They looked at mortality risk data from 1971 through 2019, and they found that around 1984, the mortality risk started increasing. In fact, mortality risk has doubled since then, which corresponds to trees living half as long.

So all that carbon that’s being trapped and stored by the trees is getting re-released into the atmosphere way sooner than it used to. To figure out what’s going on, the scientists correlated mortality risk data with a bunch of different climate-related factors, and they found that tree deaths were particularly associated with wind damage from tropical cyclones and something called the vapor pressure deficit. This is the difference between how much water the air can hold and how much it actually does.

If there’s a big deficit, the air is dry, and plants try to stay hydrated by closing up the pores that let carbon dioxide in and water out. But less carbon dioxide means less photosynthesis, which the plant needs to stay alive.

So it’s a vicious cycle: increasing temperatures increase the vapor pressure deficit, which increases tree death,  which releases more stored carbon into the atmosphere, which increases temperatures. The researchers suggest that trees that are better able to withstand water stress might be able to slow down this effect, but there are so many variables,  it’s tough to say for sure but even if that does help,  it’s just one piece of the puzzle. And when it comes to solutions to the climate crisis, there’s no time to sleep on it.

If you want to help fight the climate crisis while you keep your bedroom the perfect temperature for sleep, check out this video’s sponsor: Google. Thank you, Google for supporting this portion of the video. Google is upping their sustainability game. They’ve been carbon neutral since 2007  and are planning to eliminate operations emissions by running on clean energy every hour of every day by 2030. And you can join them without leaving your home!

Google just launched a service for  Nest thermostats called Nest Renewwhich helps support a cleaner future. Like one that automatically adjusts your thermostat to prioritize cleaner or less expensive energy.

The energy grid is often a mix of renewable energy like solar power and non-renewable energy like coal. With Nest Renew, your thermostat can make small adjustments that reduce your energy usage when the energy grid uses more non-renewable energy. You can also see when the electricity coming into your home is cleaner, which lets you take small actions like running the laundry when the grid is cleaner. And if you’re looking for new laundry machines, Google can help by providing search suggestions that highlight cost-effective and energy-efficient machines for your home.

By using Google’s sustainable features,  you can make your home greener from the appliances in it to the hours they’re working. To learn more about Google’s sustainability efforts, click the link in the description.

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